MAT 103A Practice Exam 1

Key

Problem 1:  Determine if the triangle with vertices (3,-5), (2,4), and (1,1) is isosceles, equilateral, or neither.

Problem 2:  Determine if the following are true or false.  Explain why your answer is correct.

A.  If (2,3) is a point on the graph of the function y = f(x) that is symmetric with respect to the y-axis, then (-2,-3) is also on the graph of y = f(x).

B.  Let the slope of line r be 3/2 and the slope of line s be -2/3.  If P is is the point of intersection of the two lines and if Q and R are points on lines r and s that are distinct from point Q, then the triangle with vertices P, Q, and R is a right triangle.

C.  If f(x) = x2 + 3x - k and if f(1) = 5, then f(2) = 9.

D.  A circle is never the graph of a function of y in terms of x.

E.  If f(x) is an increasing function between 3 and 7 and if f(4) = 0 then f(5) cannot be negative.

Problem 3:  List the intercepts and test for symmetry.  4x2 + 9y2 = 36

Problem 4:  The sketch below shows part of the function y = f(x) that is symmetric with respect to the origin.  Sketch the rest of the function.

sketch of graph in quadrant 1

Problem 5:  Use a calculator to sketch the graph of y = x3 - 4x2 + x + 2.  Then approximate the intercepts, the relative maximum and minimum, and where the function is increasing and where it is decreasing.

Problem 6:  A waiter receives $8 an hour in base wages plus 15% of all receipts from the tables that he serves.  Write a linear model that relates the waiter's hourly wage W when his total receipts is R dollars.

Problem 7:  Find the center and radius of the circle x2 + y2 - 10x + 4y  =  7.  Then graph the circle.

Problem 8:  Find the equation of the circle that has diameter with endpoints (-1,2) and (3,-1).

Problem 9:  Find the domain of the function

f(x) = (1-x)/sqrt(1-x)

Problem 10:  If a ball is dropped from a building its height h off the ground in feet after t seconds is h(t) = -16t2 + 320.  When will the ball hit the ground?

Problem 11:  Find the domain and range of the function shown below.  List any intercepts, symmetry with respect to the x-axis, y-axis, or the origin, any relative maximum and minimum, and the intervals where the function is increasing and where it is decreasing.

graph of the function

Problem 12:  Find the average rate of change of the function f(x)  =  x3 - 2x + 3 from -1 to 2.